1. Field
The present application relates to imaging in general, and more specifically to model-based fusion of images. Certain disclosed methods concern structure determination, including structures of biomolecules, such as proteins, peptides, lipids, polysaccharides and/or nucleic acids.
2. Related Art
In various forms of imaging technology, such as scanning probe microscopy (SPM), different sensing modalities may be used to image a particular subject. In conventional methods, each image may be interpreted individually, with only qualitative cross-referencing of various common features of the images. In SPM, the images are generally interpreted by visual observation. Interpretation of images may be time consuming and inefficient when a large amount of data must be interpreted, such as identifying one or more specific molecular structures in various samples. Cross-referencing of structural features in images captured by different scanning probe modalities, such as atomic force microscopy (AFM), scanning tunneling microscopy (STM), and/or magnetic force microscopy (MFM) is very slow and is subject to operator error or interpretation.
In determining whether a known subject is present in a sample, different sensing modalities used to image a sample are generally not combined to provide a fused image of the same region of the sample. Where multiple images of a sample are combined, this is typically accomplished by combining the different data sets on a point-by-point or pixel-by-pixel basis. However, the combination of images does not fully exploit the mutually independent information that is available in different images. Further, the combination of images on a point-by-point or pixel-by-pixel basis requires a precise alignment of the individual images to create a multi-feature image on the same grid. Such alignment is extremely difficult for SPM images of structures on a nanometer-scale, in the absence of known calibration landmarks for alignment. A need exists for methods of image fusion that utilize known structural characteristics of biomolecules to assist in identification and analysis of SPM images.